The Claim

In young, resistance-trained individuals, 8 weeks of twice-weekly leg press and leg extension training with 5 sets of 12 repetitions, performed as either traditional or cluster sets, results in significant increases in thigh lean tissue mass and rectus femoris muscle thickness under volume- and effort-matched conditions.

Source: Cluster sets and traditional sets elicit similar muscular hypertrophy: a volume and effort-matched study in resistance-trained individuals

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
59score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

In young people who regularly lift weights, performing leg exercises twice a week for 8 weeks with a specific number of sets and reps increases the size of thigh muscle and lean tissue, regardless of whether the sets are done traditionally or with short breaks between reps.

See the scientific wording

In young, resistance-trained individuals, 8 weeks of twice-weekly leg press and leg extension training with 5 sets of 12 repetitions (either as traditional or cluster sets) leads to significant increases in thigh lean tissue mass and rectus femoris muscle thickness, confirming that both protocols are effective for hypertrophy under volume- and effort-matched conditions.

Why this might work

When muscles are worked hard under load, the force pulling on muscle fibers activates signals inside the cells that tell them to build more protein. This causes the fibers to get thicker over time, increasing muscle size.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Cluster sets and traditional sets elicit similar muscular hypertrophy: a volume and effort-matched study in resistance-trained individuals

    If you're already experienced with lifting and train your legs twice a week with hard sets, your muscles grow just as much whether you take short breaks between reps or not—as long as you do the same total amount of work and push yourself just as hard.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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